The invention relates to the field of electrical plug connectors for establishing an electrical connection between two electrical regions separated from one another by a wall. The invention relates in particular to an electrical plug connector comprising a first plug connector part having electrical plug contacts, a second electrical plug connector part having electrical contact jacks, as well as a guide bushing that is designed to be passed through a mounting hole located in a wall and which at one end bears the first plug connector part and on the other end the second plug connector part, means for affixing the plug connector to the wall being assigned to same.
Such electrical plug connectors are required, for example, in the use of gear control systems in motor vehicles. In such cases, the gear wall is the wall or partition wall between an electrical plate located inside the gear housing, upon which is fitted a connector part having electrical plug contacts with a pin housing to establish electrical contact with the electrical plate. To achieve contact of the electrical plug contacts of the plug part, a plug socket part is provided that can be attached to the electrical plug contacts for providing the desired electrical plug connector with the contact jacks contained in the socket part. The socket part is arranged at one end of a set of lines whose other end is connected to the inputs and outputs of an electronic control system that monitors and controls the electronic systems within the gear housing.
Such a plug connector is known from German Utility Model DE 297 21 908 U1. For the electrical plug connector represented in this document, the plug part as described above is part of the electrical plate from which the electrical plug contacts project in the direction of the gear wall. The plug contact arrangement is bordered by a bridge-like housing wall that forms a receptacle for receiving a guide bushing. The guide bushing is arranged to project upward from the electrical plate and through the gear wall and to border the inside of the insert edge. The guide bushing is connected to the insert edge by a fastening clamp. With a section having locking grooves on the outer side, the guide bushing projects from the gear wall on the side opposite to the electrical plate. The locking grooves serve to lock a bayonet ring that is fitted to the socket part to secure the electrical plug connection created.
The bayonet ring has on its end at the plug side a support flange that is supported on the outer surface of the gear wall. The bayonet locking is designed such that, when the bayonet ring is placed or rotated to achieve locking, the guide bushing is withdrawn to a specified extent from the gear wall. To the gear wall are attached elements which act like groove pins and facing the electrical plate, which engage into centering and fastening sockets corresponding to the electrical plate. When the bayonet ring is locked to the guide bushing, thus causing the guide bushing to be withdrawn or the electrical plate to be pulled toward the gear wall, the elements with similar action as groove pins are pressed into the centering and fastening sockets fitted to said elements. After the bayonet ring is set in place, the electrical plug connector as well as the electrical plate for the connector part are then fastened to the gear wall.
A disadvantage of this known plug connector is that the guide bushing must be attached to the pin housing by means of a fastening clamp in order to mount the plug connector. This known plug connector is therefore not suitable for such uses in which access cannot be gained behind the wall separating the two electrical regions in order to establish electrical contact. In addition, the elements with similar action as groove pins that are used for attachment to the partition wall sometimes do not represent a completely ideal solution. In a so-called xe2x80x9cblind mountingxe2x80x9d to establish electrical contact between the two plug connector sites, whereby the plug connector part located behind the wallxe2x80x94the pin housingxe2x80x94is reachable only through the mounting hole through the wall, it cannot be determined if the electrical plate has actually been attached correctly to the inner side of the wall.
The reliability of the plug connector on the wall, disclosed in DE 297 21 908 U1, is strongly dependent on the quality of the frictional grip between the outer surface of the elements which act like groove pins and the cylindrical inner surfaces of the centering and fastening sockets. In order to produce a connection that withstands strong pull-out forces, the connection requires a dimensional configuration of the elements which act like groove pins and the centering and fastening sockets such that the former must be pressed with strong force into the latter. As the number of fastening points used increasesxe2x80x94approximately three being customarily usedxe2x80x94the force required to produce a connection also increases. Because of production tolerances in the arrangement of the centering and fastening sockets and the elements which act like groove pins, the electrical plate can be subjected to undesired tension after being placed on the gear wall.
Proceeding from the prior art previously discussed, the objective of the invention is thus to develop a generic electrical plug connector as described hereinabove that not only assures a secure xe2x80x9cblind mounting,xe2x80x9d but also allows a tension-free attachment to the partition wall.
This objective is achieved by the invention in that the one plug connector part and the guide bushing have cooperating connecting means which if the guide bushing is rotated connect said two parts such that they are aligned with the longitudinal axis of the guide bushing, and that the plug connector comprises holding means with which the plug connector part is held on the side of the wall such that it can be displaced in the direction of the longitudinal axis of the guide bushing, with a stop for limiting the distance along which the plug connector can be moved away from the guide bushing, and that means for affixing the guide bushing to the side of the wall opposite the plug connector are assigned to said guide bushing.
For the electrical plug connector according to the invention, connection means for fastening the guide bushing to the plug connector part located behind a partition wall are used such that the two said parts can be connected without additional elements. Moreover, the connection between the guide bushing and the connection means is established by rotating the guide bushing so that a connection between the two said parts can be made by rotation of the guide bushing. If, for some reason, this rotation cannot be performed in whole or in part, the assembler is aware that a proper attachment is not possible. A holder is provided to assure proper alignment of the plug connector part, located on the inaccessible side of the wall, with the mounting hole. The plug connector part is supported with freedom to move by said holder in the direction of the longitudinal axis of the guide bushing. An arrangement of stops limits the distance along which the plug connector part can be moved away from the guide bushing, so that during mounting of the guide bushing the plug connector part is not pushed away. Means for attaching the plug connector to the wall are assigned to the guide bushing to allow an attachment of the guide bushing to the accessible side of the wall. The plug connector is thus attached to the wall in a region in which the plug connector is always accessible, thereby enabling the plug connector to be easily detached from the wall.
The connection means for connecting the guide bushing that passes through the wall to the plug connector part located behind said wall can be designed, for example, as a screw thread or a bayonet locking. In the development of a bayonet locking, it is useful to design the locking slot as an annular body and to provide same on the plug connector part, and to provide radially projecting locking pegs on the guide bushing. Provision of a bayonet locking allows the guide bushing to be quickly and securely mounted to the plug connector part. Based on an insertion opening for introducing the locking pegs, the locking slot of the plug connector part can be designed to lie in a plane perpendicular to the longitudinal axis of the guide bushing, or with an inclined section that is aligned crosswise to the longitudinal axis of same and that slopes away from the insertion opening. In the latter case, during attachment of the guide bushing the plug connector part is pulled toward the guide bushing, so that the plug connector part can be brought from a mounting position in the holder to a plug connector position.
As an example of a means for affixing the guide bushing to the accessible side of the wall, a fastening bracket that is integrally formed radially to the guide bushing can be provided with an opening facing the wall, into which a screw can be inserted or is already inserted to affix the guide bushing on the wall. By attachment of the guide bushing, along with the plug connector fastened thereto, to the wall, the entire plug connector is affixed to the wall.
As a holding means for the plug connector part, a plurality of holding feet can be provided that are held, with some play with regard to their width, in a guiding groove of a holder that is provided on the plug connector part. As an example, the feet can be integrally formed onto a base plate of the plug connector part and held in the guiding groove by virtue of their material elasticity.
An electrical connection between the inaccessible plug connector part, which, for example, can be the plug part provided with a pin housing, and the electrical/electronic components placed on a circuit support at a distance from the plug connector part is achieved by means of a flexible conductor such as a foil conductor. Thus, vibrations occurring between the unit bearing the electrical/electronic components and the partition wall are not transmitted from one unit to the other.